JP7365837B2 - Piping end sealing device - Google Patents

Description

The present invention relates to a device for sealing an end of a pipe.

In nuclear power generation facilities, etc., it is sometimes required to seal the ends of piping.
In the sealing device disclosed in FIG. 1 of Patent Document 1, the end of the pipe is sealed by interposing an O-ring between the closing member and the outer periphery of the end of the pipe.
In the sealing device disclosed in Patent Document 2, an elastic seal member made of rubber is arranged inside the end of the pipe, and this elastic seal member is compressed in the axial direction to expand the diameter, thereby sealing the inside of the end of the pipe. This seals the end of the pipe.

Japanese Unexamined Patent Publication No. 176891/1983 Japanese Patent Application Publication No. 63-275931

In the sealing device disclosed in FIG. 1 of Patent Document 1, since sealing is performed using only an O-ring, good sealing performance cannot be ensured over a long period of time.
The sealing device disclosed in Patent Document 2 is used to temporarily seal the end of a pipe, and the support of the elastic seal member is unstable, making it difficult to seal the end of the pipe over a long period of time. Not suitable.

The present invention has been made to solve the above problems, and is a device for sealing the end of a pipe.
a closing member having a closing part disposed opposite to the opening of the pipe end; and a cylindrical part disposed radially outward of the pipe end;
Fixing means for fixing the cylindrical portion of the closing member to the pipe end;
a sealing structure that is supported by the closing member and seals the end of the piping;
The sealing structure is arranged in an axial direction of the piping end by passing through an elastic sealing member disposed inside the piping end, an insertion hole of the elastic sealing member, and an insertion hole of the closing part of the closing member. a rod extending into the rod, a pressing member attached to an inner end of the rod, and a pressing member connected to an outer end of the rod, and by drawing the pressing member toward the closing part of the closing member through the rod. , an attracting means for compressing the elastic seal member in the axial direction between the closing portion of the closing member and the pressing member, thereby bringing the expanded diameter elastic seal member into close contact with the inner periphery of the pipe end; It is characterized by having the following.

According to the above configuration, by covering the elastic sealing member that tightly contacts the inner periphery of the pipe end with the closing member disposed at the pipe end and supporting it via the rod, stable and good sealing performance can be achieved over a long period of time. can be secured.
Preferably, the attracting means is a nut threaded onto the outer end of the rod.

Preferably, an annular filling space surrounded by the rod is formed in the closing portion of the closing member at an axially intermediate portion of the insertion hole, and the filling space is filled with a sealing material.
According to the above configuration, even if the elastic sealing member deteriorates due to long-term use and a leakage path is formed between the inner periphery of the insertion hole of the elastic sealing material and the rod, the gap between the inner periphery of the insertion hole of the closing member and the rod However, since the filling space is sealed by the sealing material, good sealing performance can be ensured.

More preferably, the closing portion of the closing member has a pressing portion having a smaller diameter than the piping end, and the pressing portion protrudes toward the elastic sealing member and enters the piping end, so that the pressing portion and the An annular space is formed between the piping end and the annular space is also filled with the sealing material.
According to the above configuration, even if the elastic seal member deteriorates due to long-term use and a leak passage is formed between the inner periphery of the pipe end and the elastic seal material, the sealing material filled in the annular space allows the pipe end to Since the space between the closing members is sealed, good sealing performance can be ensured.

More preferably, an injection port for injecting the sealing material into the filling space is formed in the closing portion of the closing member, and the injection port is provided between the annular space and the injection port. A communication passage is formed for conveying the sealing material from the annular space into the annular space.
According to the above configuration, two filling spaces can be simultaneously filled with the sealant using a common injection port.

Preferably, the cylindrical portion of the closing member includes a first cylindrical portion that is continuous with the closing portion and into which the pipe end is inserted, and a first cylindrical portion that is continuous with the first cylindrical portion via a step portion and has a diameter smaller than that of the first cylindrical portion. the fixing means has a fixing structure including an inner ring, an outer ring, and a tightening ring, and the inner ring has a tapered outer surface and a circumferentially divided taper. and a cylindrical threaded part connected to the tapered part, and the outer ring is composed of a plurality of pieces divided into a plurality of pieces in the circumferential direction, each piece having a tapered inner surface. The tightening ring has a tapered part in contact with the outer surface of the inner ring and an engaging part connected to the tapered part, and the tightening ring is screwed into the threaded part of the inner ring, and the tightening ring is screwed into the threaded part of the inner ring. The tapered portion of the inner ring and the tapered portion of the outer ring are engaged with the engaging portion so as to be relatively rotatable and immovable in the axial direction. When the tightening ring is rotated, the inner ring and the outer ring move relative to each other in the axial direction, so that the inner ring of the tapered part of the inner ring is positioned between the inner ring and the outer circumference of the pipe end. and the outer surface of the tapered portion of the outer ring is pressed against the inner periphery of the second cylindrical portion.
According to the above configuration, the closing member can be smoothly and easily fixed to the end of the pipe at the site.

According to the present invention, the end of the pipe can be well sealed for a long period of time.

FIG. 1 is a longitudinal cross-sectional view showing a pipe end sealing device according to an embodiment of the present invention in a state before being filled with a sealant. FIG. 2 is a sectional view taken along the line II-II in FIG. 1. FIG. FIG. 3 is a longitudinal cross-sectional view showing the sealing device in a state after being filled with a sealant.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A piping end sealing device according to an embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 shows an end 1 of a pipe cut in a nuclear power generation facility and a sealing device 2 for sealing this pipe end 1. The sealing device 2 includes a closing member 10, an O-ring 20 incorporated in the closing member 10, a fixing structure 30 (fixing means) for fixing the closing member 10 to the pipe end 1, and a sealing device for sealing the pipe end 1. It is provided with a sealing structure 40 for sealing, and is assembled in advance before being attached to the piping end 1.

Structure of the closing member 10 The closing member 10 integrally includes a disk-shaped closing portion 11 and a cylindrical portion 12. The cylindrical portion 12 includes a first cylindrical portion 12a connected to the closing portion 11, and a second cylindrical portion 12c connected to the first cylindrical portion 12a via a step portion 12b and having a larger diameter than the first cylindrical portion 12a. There is. A pressing portion 13 is formed at the center of the inner surface of the closing portion 11 and protrudes coaxially with the cylindrical portion 12 .

The inner diameter of the first cylindrical portion 12a is approximately equal to or slightly larger than the outer diameter of the pipe end 1. An annular groove 12x is formed in the inner peripheral surface of the first cylindrical portion 12a, and an O-ring 20 is accommodated in this annular groove 12x.

The outer diameter of the pressing portion 13 is smaller than the inner diameter of the first cylindrical portion 12a. An insertion hole 14 extending in the axial direction is formed in the center of the pressing portion 13 . The insertion hole 14 has approximately the same diameter as or slightly larger than the diameter of a rod 42, which will be described later, and is adapted for the rod 42 to be inserted therethrough.

An annular filling space 15 having a larger diameter than the insertion hole 14 is formed in the closing portion 11 at a midway portion of the insertion hole 14 . The closing portion 11 is further formed with an injection port 16 and a discharge port 17 that extend in the radial direction. The injection port 16 and the discharge port 17 connect the filling space 15 with the outside, face each other in the radial direction, and are located on the same straight line.
Furthermore, two through holes are formed in the closing portion 11, passing through the injection port 16 and the discharge port 17 in the axial direction. The outer ends of these through holes are closed by press-fitting plugs 18a and 18b, and are provided as communication passages 19a and 19b which function as will be described later.

Structure of the fixing structure 30 The fixing structure 30 itself is known and commercially available products can be used. The fixing structure 30 is for fixing the closing member 10 to the pipe end 1 and includes an inner ring 31, an outer ring 32, and a tightening ring 33.
The inner ring 31 has a tapered portion 31a and a threaded portion 31b that are adjacent to each other in the axial direction. The tapered portion 31a is divided into a plurality of parts in the circumferential direction by slits (not shown) extending in the axial direction. The outer surface of the tapered portion 31a is tapered such that the diameter becomes smaller toward the threaded portion 31b. A male thread 31x is formed on the outer circumferential surface of the threaded portion 31b.

The outer ring 32 is composed of a plurality of pieces that are divided in the circumferential direction and extend in the axial direction, and each piece has a tapered portion 32a and an engaging portion 32b. The inner surface of the tapered portion 32a is tapered such that the diameter becomes smaller toward the engaging portion 32b when the plurality of pieces are assembled. The taper angles of the tapered portion 31a of the inner ring 31 and the tapered portion 32a of the outer ring 32 are equal. A recess 32y extending in the circumferential direction is formed on the inner periphery of the engaging portion 32b.

The tightening ring 33 has a female thread 33x formed on its inner periphery to be screwed into the male thread 31x of the inner ring 31, and an annular protrusion 33y formed on its outer periphery. The plurality of concave portions 32y of the outer ring 32 are engaged with the annular convex portion 33y , so that the outer ring 32 and the tightening ring 33 are connected to each other in an axially immovable and relatively rotatable manner. ing. The engaging portion 32b of the outer ring and the tightening ring 33 have, for example, a hexagonal outer periphery, on which a tool or the like can be hung.
The tapered portions 31a and 32a of the inner ring 31 and outer ring 32 of the fixing structure 30 are housed inside the second cylindrical portion 12c of the closure member 10 in a joined state.

Composition of Sealing Structure 40 The sealing structure 40 includes a cylindrical rubber elastic sealing member 41, a threaded rod 42 (rod), a pressing member 43, a nut 44 (retracting means), and a washer 45. are doing. At the center of the elastic seal member 41, an insertion hole 41a is formed which penetrates in the axial direction. The inner diameter of this insertion hole 41a is approximately equal to the outer diameter of the threaded rod 42.

The threaded rod 42 is inserted through the insertion hole 41a of the elastic seal member 41 and the insertion hole 14 of the closure part 11 of the closure member 10, and its inner end protrudes from the axially inner end surface of the elastic seal member 41, and its outer end protrudes from the outer surface of the closure part 11.
A pressing member 43 is screwed into the inner end of the threaded rod 42 and fixed by welding. The pressing member 43 has a flat surface that contacts the inner end surface of the elastic sealing member 41. A nut 44 is screwed onto the outer end of the threaded rod 42. A washer 45 is interposed between the pressing portion 13 of the closing portion 11 and the outer end surface of the elastic seal member 41.

Step of attaching the sealing device 2 to the pipe end 1 The sealing device 2 assembled as described above is mounted to the pipe end 1. Specifically, the sealing device 2 is moved in the axial direction with the fixing structure 30 facing the pipe end 1. As a result, the pipe end 1 passes through the inner ring 31 of the fixed structure 30, passes through the first cylindrical portion 12a of the closing member 10, and its tip hits the inner surface 11a of the closing portion 11. In this state, the closing part 11 of the closing member 10 is arranged to face the opening of the pipe end 1 and closes this opening. The tapered portion 31a of the inner ring 31 and the tapered portion 32a of the outer ring 32 are accommodated between the second cylindrical portion 12c of the closing member 10 and the outer periphery of the pipe end portion 1 in a joined state.

By the axial movement of the sealing device 2, the elastic sealing member 41 is inserted into the pipe end 1. Note that the outer diameter of the elastic seal member 41 is slightly larger than the inner diameter of the pipe end 1, and therefore, the elastic seal member 41 is inserted into the pipe end 1 with friction. The elastic seal member 41 does not rotate idly. The outer diameter of the elastic seal member 41 in its natural state may be made slightly larger than the inner diameter of the pipe end 1, or the elastic seal member 41 may be compressed in the axial direction by tightening the nut 44 as described later. The outer diameter may be slightly larger than the inner diameter of the pipe end 1.

Next, when the tightening ring 33 is rotated relative to the outer ring 32 in the tightening direction, the inner ring 31 is rotated in the axial direction relative to the outer ring 32 due to the screwing action of the inner ring 31 and the tightening ring 33. Due to the tapering action of the tapered portions 31a and 32a, each piece of the outer ring 32 is displaced radially outward, and each divided portion of the tapered portion 31a of the inner ring 31 is displaced radially inward. As a result, the outer surface of the tapered portion 32a of the outer ring 32 strongly contacts the inner circumferential surface of the second cylindrical portion 12c of the closing member 10, and the inner surface of the tapered portion 31a of the inner ring 31 strongly contacts the outer circumferential surface of the pipe end 1. Therefore, the closing member 10 is firmly fixed to the pipe end 1.
As described above, the fixing structure 30 allows the closing member 10 to be firmly fixed to the pipe end 1 with a simple operation without using welding.

Next, when the nut 44 is turned in the tightening direction, the pressing member 43 is drawn toward the closing portion 11 of the closing member 10 (that is, rightward in FIG. 1) via the threaded rod 42. As a result, the inner end surface of the elastic seal member 41 is pressed by the pressing member 43, and the outer end surface is pressed by the pressing portion 13 of the closing member 10 via the washer 45, so that the elastic seal member 41 is compressed in the axial direction. As a result, the elastic seal member 41 tries to swell (expand its diameter) in the radial direction, so that its outer circumferential surface tightly adheres to the inner circumferential surface of the pipe end 1.

There are two possible leakage paths for fluid from the sealing pipe end 1 of the sealing device 2. The first leakage path is a path between the threaded rod 42 and the inner periphery of the insertion hole 41 a of the elastic seal member 41 and the insertion hole 14 of the closing portion 11 . This first leakage path is caused by the pressing member 43 coming into close contact with the inner end surface of the elastic sealing member 41 with a strong force, and the elastic sealing member 41 being subjected to an axial compressive force so that the inner periphery of the insertion hole 41a is connected to the threaded rod 42. It is blocked by coming into close contact with the
The second leak path is a path between the outer periphery of the elastic seal member 41 and the inner periphery of the pipe end 1. This second leakage path is blocked by the elastic seal member 41 coming into close contact with the inner periphery of the pipe end 1 with strong force as described above.

As described above, the sealing structure 40 allows the pipe end 1 to be well sealed. Moreover, since the closing member 10 fixed to the pipe end 1 by the fixing structure 30 supports the elastic sealing member 41 via the rod 42, good sealing performance by the sealing structure 40 can be stably maintained over a long period of time. I can do it.

Further enhancement of sealing performance In this embodiment, good sealing performance over a longer period of time is ensured, assuming deterioration of the elastic seal member 41. The details will be explained below.
After tightening the nut 44 and completing the sealing work with the elastic seal member 41 as described above, the sealing material 50 (caulking material: shown in FIG. 3) is inserted from the injection port 16 as shown by arrow A in FIGS. (only shown). This sealing material 50 has viscosity and fluidity, enters the annular filling space 15 from the injection port 16, and fills the filling space 15. It also enters the annular space 25 formed between the pressing part 13 of the closing member 10 and the piping end 1 from the injection port 16 through the communication passage 19a, and is filled into the annular space 25. The sealing material 50 fills the filling space 15 and then is discharged through the discharge port 17, and also fills the annular space 25 and is discharged through the discharge port 17 via the communication passage 19b. After confirming that the filling space 15 and the annular space 25 are filled based on the discharge status of the sealant 50 from the discharge port 17, the injection of the sealant 50 is finished.

Even if the elastic seal member 41 deteriorates due to long-term use, the sealing material 50 filled in the filling space 15 can reliably prevent fluid from leaking from the first leak path described above. Furthermore, the sealing material 50 filled in the annular space 25 can reliably prevent fluid from leaking from the second leakage path.

The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit thereof.

INDUSTRIAL APPLICATION This invention can be applied to the apparatus which seals the end of piping.

1 Piping end 2 Sealing device 10 Closing member 11 Closing part 12 Cylindrical part 12a First cylindrical part 12b Step part 12c Second cylindrical part 13 Pressing part 14 Insertion hole 15 Filling space 16 Injection port 19a Communication passage 25 Annular space 30 Fixed Structure (fixing means)
31 Inner ring 31a Tapered part 31b Screwing part 32 Outer ring 32a Tapered part 32b Engaging part 33 Tightening ring 40 Sealing structure 41 Elastic sealing member 42 Threaded rod (rod)
43 Pressing member 44 Nut (attraction means)
50 Sealing material

Claims (4)

In a device that seals the end of a pipe,
a closing member having a closing part disposed opposite to the opening of the pipe end; and a cylindrical part disposed radially outward of the pipe end;
Fixing means for fixing the cylindrical portion of the closing member to the pipe end;
a sealing structure that is supported by the closing member and seals the end of the pipe;
Equipped with
The above sealing structure is
an elastic seal member disposed inside the end of the pipe;
a rod extending in the axial direction of the piping end through the insertion hole of the elastic sealing member and the insertion hole of the closing portion of the closing member;
a pressing member attached to the inner end of the rod;
The elastic seal member is connected to the outer end of the rod and is drawn between the closing portion of the closing member and the pressing member by drawing the pressing member toward the closing portion of the closing member through the rod. an attracting means for compressing the elastic seal member in the axial direction and thereby bringing the expanded diameter elastic seal member into close contact with the inner periphery of the pipe end;
has
the attracting means is a nut screwed onto the outer end of the rod;
A filling space including an annular recess and surrounding the rod is formed on the inner periphery of the axially intermediate portion of the insertion hole in the closing portion of the closing member, and the filling space is filled with a sealing material. . A sealing device for a pipe end, characterized in that a space between the closing portion and the rod is sealed . The closing portion of the closing member has a pressing portion having a smaller diameter than the piping end, and the pressing portion protrudes toward the elastic sealing member and enters the piping end, and the pressing portion and the piping end are connected together. According to claim 1 , an annular space is formed between the pressing part and the piping end, and the annular space is also filled with the sealing material, thereby sealing the space between the pressing part and the pipe end part. A sealing device for the end of a pipe. An injection port for injecting the sealing material into the filling space is formed in the closing portion of the closing member, and between the annular space and the injection port, the sealing material from the injection port is formed. 3. The piping end sealing device according to claim 2 , further comprising a communication passage for sending material into the annular space. The cylindrical portion of the closing member includes a first cylindrical portion that connects to the closing portion and into which the pipe end is inserted, and a second cylindrical portion that connects to the first cylindrical portion via a stepped portion and has a larger diameter than the first cylindrical portion. having a cylindrical portion;
The fixing means has a fixing structure including an inner ring, an outer ring, and a tightening ring,
The inner ring has a tapered part whose outer surface is tapered and is divided in the circumferential direction, and a cylindrical threaded part connected to the tapered part,
The outer ring is composed of a plurality of pieces that are divided into a plurality of pieces in the circumferential direction, and each piece has a tapered part whose inner surface is tapered and comes in contact with the outer surface of the inner ring, and an engaging part that is connected to the tapered part. and has
The tightening ring is screwed into the threaded portion of the inner ring, and is engaged with the engaging portion of the outer ring so as to be relatively rotatable and immovable in the axial direction,
With the tapered part of the inner ring and the tapered part of the outer ring disposed between the second cylindrical part of the closing member and the outer periphery of the end of the piping, as the tightening ring rotates. Due to the relative axial movement of the inner ring and the outer ring, the inner surface of the tapered portion of the inner ring is pressed against the outer periphery of the pipe end, and the outer surface of the tapered portion of the outer ring is pressed against the second cylindrical portion. The sealing device for a pipe end according to any one of claims 1 to 3, wherein the device is pressed against the inner periphery of the pipe end.

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